We are doing obedience classes and Indigo will not sit, she looks at me like "lady stop playing with my treats, now cut of this sit foolishness out, and feed me human!

" any suggestions? The trainer is not much help, she just say it takes 2 weeks for dogs to learn, but all the other dogs got it, and I know Indi (15 weeks) is smarter than the average bear.
btw, we're the only little one in the class, i can tell the trainer prefers the bigger dogs.